Backpack



FIG. 1 is a front perspective view of the backpack, showing the new design;

FIG. 2 is a rear perspective view of FIG. 1;

FIG. 3 is a front elevational view of FIG. 1;

FIG. 4 is a rear elevational view of FIG. 1;

FIG. 5 is a left-side elevational view of FIG. 1;

FIG. 6 is a right-side elevational view of FIG. 1; and,

FIG. 8 is a bottom plan view of FIG. 1.

The broken lines representing a logo in the FIGS. 1, 3 and 7 form no part of the claimed design. The remaining broken lines represent stitching and do form part of the claimed design. 

CLAIM I claim the ornamental design for a backpack, as shown and described. 